As the time when someone can protect his rights is limited by law and usually is not longer than 3 years, protection of rights when that period has expired is permitted only in several occasions.

One of such occasions not apparantly specified by law is a case when someone wants to recover a debt which appeared as a credit,
given for a limited time, with condition that when the specified time expires the credit should be returned when called for.

Finally only in court with supervisory authority powers we could proove that law protection for "poste restante" obligation is not limited by the mentioned above 3 years limitation.